SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7960a42b202d3b4dd2ba06f1f4390799d261efa631cb64ba5326628d69f7b885' 
  AND token = 'yQiSgFqZZKt4eOcOM9xAnla6j3bxUOq4IA0KGM0PKoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}